Why are Germans so excited about Barack Obama?

Today in Berlin, Barack Obama meets with German Chancellor Angela Merkel and Foreign Minister Walter Steinmeier. He's also holding the only major public event of his trip at the Victory Tower (with room for an audience of tens of thousands). So what's gotten into Germans? And why are German citizens and top officials making time for a presidential candidate?

Guest: Arne Delfs, German Politics and Economics Editor at the Financial Times Deutschland